# xarray.CFTimeIndex.drop_duplicates

#### CFTimeIndex.drop_duplicates(, keep='first')[[source]](https://github.com/pydata/xarray/blob/main/xarray/../.pixi/envs/doc/lib/python3.15/site-packages/pandas/core/indexes/base.py#L3000-L3053)

Return Index with duplicate values removed.

The `keep` parameter controls which duplicate values are removed.
The original Index is not modified.

* **Parameters:**
  **keep** (`{'first', 'last', ``False`}\`\`, *default* `'first'`) –
  - ‘first’ : Drop duplicates except for the first occurrence.
  - ‘last’ : Drop duplicates except for the last occurrence.
  - `False` : Drop all duplicates.
* **Returns:**
  [`Index`](https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.Index.html#pandas.Index) – A new Index object with the duplicate values removed.

#### SEE ALSO
`Series.drop_duplicates`
: Equivalent method on Series.

`DataFrame.drop_duplicates`
: Equivalent method on DataFrame.

`Index.duplicated`
: Related method on Index, indicating duplicate Index values.

### Examples

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Generate a pandas.Index with duplicate values.

```pycon
>>> idx = pd.Index(["llama", "cow", "llama", "beetle", "llama", "hippo"])
```

The keep parameter controls  which duplicate values are removed.
The value ‘first’ keeps the first occurrence for each
set of duplicated entries. The default value of keep is ‘first’.

```pycon
>>> idx.drop_duplicates(keep="first")
Index(['llama', 'cow', 'beetle', 'hippo'], dtype='str')
```

The value ‘last’ keeps the last occurrence for each set of duplicated
entries.

```pycon
>>> idx.drop_duplicates(keep="last")
Index(['cow', 'beetle', 'llama', 'hippo'], dtype='str')
```

The value `False` discards all sets of duplicated entries.

```pycon
>>> idx.drop_duplicates(keep=False)
Index(['cow', 'beetle', 'hippo'], dtype='str')
```

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